Sea Ice Poll

Many of you are already aware that the WUWT blog regularly conducts a poll to predict the minimum sea ice extent we’ll see later this year, and their poll result is submitted as a prediction to ARCUS. What a great idea! Not only does it gauge the opinion of the WUWT readers about a very precise quantity, it’s also fun.

So let’s have fun too. I don’t have the convenient survey program or plug-in (and I’m really not that interested in it), so you vote by commenting. After a reasonable voting period I’ll tally the answers and report the result. The question is: what will be this year’s minimum sea ice extent? It asks for a number so give a numerical answer. If you want to predict the upcoming minimum sea ice area as well that’s fine, but the question is about extent. Units are millions of square kilometers.

Just to be annoying, is that NSIDC extent or JAXA as they are a little different (~0.7 Mkm^2).
I would assume you intend NSIDC, that having a longer record (& not having suffered a satellite failure/change in the last year).

FWIW, on the last ASI Blog polls (new one coming up when the latest SEARCH SIO is published) I voted between I voted ‘between 3.0 and 3.2 million km2’ for the CT SIA daily minimum, and ‘between 4.50 and 4.75 million km2’ for the NSIDC monthly minimum.

I think I will now revise those a notch downwards and vote ‘between 2.8 and 3.0 million km2’ for the CT SIA daily minimum, and ‘between 4.25 and 4.5 million km2’ for the NSIDC monthly minimum.

These are the NSIDC September monthly average sea ice extent minimums in the 2005-2011 period:

Extent: 4.31 million km2 (no record. The winds in 2007 were thread-the-needle accurate in driving sea ice out of the Arctic basin. Absolutely freakish for almost a month. The near record this year will be more impressive due to the fairly uncooperative weather.

Those are minimal numbers for area and extent (not sept. average). I just used current CT anomaly (on aug 6th) and assumed it would hold to the end of melt season. Then I used ratio of extent vs. area (used IJIS values) from last year to calculate the extent (not very good method, there are better, but this is the best I can do).

Can we wait until after the storm? If not, I vote 4.1 M sq km for September NSIDC average extent (with daily minimum breaking below 4.0M at some point).

The storm will smash the pack, and it is likely that the ice concentration at the North Pole could be less than 80% before this melt season is over (I don’t think we see full open water).

As a result of the massive ice cap loss:
The NH jet stream will have higher amplitude Rossby waves, and serious blocking events will cause extreme weather events across the NH.
Odds are 50/50 we will get a snowmaggedon early this winter in the US, with warm winter weather in Europe. If El Nino develops this winter, next year will see yet another severe drought in the US, likely centered in the Southeast. The Southeast US will break the highest regional temperature spring and summer records set in 2011 (spring) and 2010 (summer).

OK, the storm took out a lot ice extent, so the last week lost 930k sq km, almost reaching a Megaweek Loss level of a million. Normally, we would expect to see losses of about 600k, so this lowers the expected minimum considerably.

Next up, an Arctic Dipole Anomaly. Given how badly the Central Arctic Basin pack was damaged, this could put open water over the North Pole this year… we should know more about this by Tuesday, the first real day of the Arctic DA.

Given current extent, and estimating 80k loss per day, we should break the previous extent minimum by August 25th, at the latest, and with slowing as we run out of ice to melt, hit 4.0 M by September 1st. Anyone, including me, who had NSIDC estimates for September higher than 4.0, needs to revise them down.

Bit off the topic here, but there is a physical basis why a quadratic function fits the Arctic sea ice trend, rather than say, having a linear decline (I assume Arctic temperature increase has been close to linear)?

At some point, I assume Arctic sea ice decline will no longer follow a quadratic function. If it still does, it looks like we may get a sea ice minimum of 0 at the end of the 2020s.

Any smooth function can be well approximated over a narrow argument range by a linear function, the first two terms of a Taylor expansion: this is called linearization. When the argument range gets broader, linear will get imprecise. The minimum incremental step to make the approximation precise again, is going to a quadratic function. That’s what’s happening here.

Physically, something like a logistic function would probably make more sense. But also that is locally well approximated by a parabola. For now :-)

My earlier prediction for the average monthly extent reported by NSIDC was made using the same method as tamino used last year, a quadratic fit, and was 4.45 million km^2. Now, using Year^2 and Area/Extent as predictors, I predict a September monthly average of 4.35 million km^2.

I’ve been guessing 4.4 million km2 for extent “if the weather doesn’t do something drastic.”

Although it looks like the weather is indeed doing something drastic, I’ve committed to that guess elsewhere so I suppose I’ll leave it alone…but like many others, I’m extremely curious to see what things look like after the storm.

If the weather turn milder as have been until yesterday, I expect a resulting extent minimum similar to 2007 (but with a different spatial distribution, being it more alike the 2008 ice distribution), ….

on the other hand, if the current Arctic cyclone remains as strong as was yesterday for a few days more, and then is followed by an anti-cyclone/Dipole Anomaly, I expect a massacre, with extent minimum below 4*10^6 km^2.

By the way, it seems that even an extreme record low will not wake up the WUWT crowd to reality. They already have put a countdown to ZERO sea ice extent/area for September 2012 in an attempt to ridicule all the people concerned about Arctic sea ice, as if most climate models would have predicted a complete summer meltdown in 2012:

That is not true. What the National Geographic was reporting
was a possible result of the combination of a strong melting trend with unfavorable climate variability, quoting NASA climate scientist researcher Jay Zwally who found that was possible an almost complete meltdown as early as 2012.

By 2008 he coincided with Professor Wieslaw Maslowski of the US Navy that the most extreme case was a complete melt not in 2012, but in 2013:

This scenario was a bit too pessimistic, but we could have been on track to that if we have had extreme 2007-like weather between 2008 and 2012 instead of the actual moderate weather observed.

A more realistic date for almost complete summer melt is (absent a monster volcanic eruption or a nuclear war, of course) is at the mid-2010s (2015-2016 as most likely date). Of course a strip of ice north of Greenland and Canadian Archipielago will remain for many years more as the skeleton of a former alive body for some more time.

If the weather turn milder as have been until yesterday, I expect a resulting extent minimum similar to 2007 (but with a different spatial distribution, being it more alike the 2008 ice distribution), ….

on the other hand, if the current Arctic cyclone remains as strong as was yesterday for a few days more, and then is followed by an anti-cyclone/Dipole Anomaly, I expect a massacre, with extent minimum below 4*10^6 km^2.

By the way, it seems that even an extreme record low will not wake up the WUWT crowd to reality. They already have put a countdown to ZERO sea ice extent/area for September 2012 in an attempt to ridicule all the people concerned about Arctic sea ice, as if most climate models would have predicted a complete summer meltdown in 2012:

That is not true. What the National Geographic was reporting
was a possible result of the combination of a strong melting trend with unfavorable climate variability, quoting NASA climate scientist researcher Jay Zwally who found that was possible an almost complete meltdown as early as 2012.

By 2008 he coincided with Professor Wieslaw Maslowski of the US Navy that the most extreme case was a complete melt not in 2012, but in 2013:

In a dramatic break of tradition, and in order to counteract the excessive alarmism on this site, which is statistically an impossible fact considering the general tone of comments on various non-alarmist websites, I’m no longer suggesting the minimum of exactly 4000000km^2 for the minimum extent of the year, which is bound to happen one of these years, but opt out to the next ordinal number exponential and guessing for a minimum of 5000000 km^2 of extent. This lethargical prognosis is acquired through careful analysis of several law-abiding comments in US chambers of government, but is though accompanied with a WAG of CAPIE of 40 on minimum date in order to get it published here on this evil nest of properly applied statistics and a horrendous center of accurately presented information that has previously been frighteningly precise in their alarmist predictions. (hope the comment makes it, saving a copy)

Tamino – it’s off topic but I can’t find anywhere else to post. I would like you to elaborate (please) in order to give me some grounding in relation to the debate about whether or not AGW/temperature rise (globally) but be regarded as stochastic process – and by implication therefore random and not predictable.

I’m not a statistician but a physicist. I understand how stochastic (random) processes work in relation to, say, brownian motion or the trajectory of a particle through a nucleus. But I really struggle to see how the basic physics of climate (net energy in from sun – insolation – must be radiated away to maintain a thermal equilibrium – GHGs retain that radiation resulting in a higher net heat content) can be described as such.

Obviously there are “random” processes (ENSO and other oceanic and atmospheric dynamics) that can move that heat around and so produce apparently stochastic trend temperature outcomes in certain locations (so you could get a “trend” locally that is not necessarily a reflection of any underlying driver just statistically be a stochastic trend). But how could this be reflected in GLOBAL temperatures which are, by defintion, averages over both space and time?

I am not sophisticated enough in my statistics to know how to test whether or not statistically a measured outcome (let’s say global temperature) is stochastic in nature as opposed to being driven by an underlying physical process overlaid with “natural” (random) variation. But it’s the latter that my physics brain is telling me what is going on. Arguments to the contrary seem to me to be pitting statisics against physics. And given the very large database of measurements for both temperature, heat content and GHG levels across the globe and across history we have I can’t see that any random process is physically capable of producing the results we see.

Would appreciate your comments either on this thread or another or to me email [(email removed)]

Numeric guesses are not appropriate because the system is highly non-linear. That is, any kind of a number would be a guess, but its format would imply a higher accuracy than intended. This is the first time we have run this physical model, “AGW”, so we do not have much experience with it. And, the computer models have a low skill at predicting the behavior of the physical model.

I’m speculating that the cyclone we’re seeing this year is at least partially caused by the fact that we’re now seeing open water most of the way around the ice. The combination of those warmer waters and the cooler ice may be creating a new dynamic.

This is totally speculation on my part (and why I say I’m going way out on a limb) but it may be possible that we would see similar conditions repeating each year. If that were to happen I think it would lead to a very rapid break up and melting of the remaining ice multi year ice.

A partial recovery would certainly be in line with what we’ve seen in the past. If we’re moving into a new phase of ice loss then a partial recovery may not be in the cards.

The Arctic ice will freeze again;
The question is, “How much?” (Not “When?”)
Its volume’s smaller every year,
And forecasts make it very clear
That someyear soon, we’ll see no more
Of all that ice we saw before.
A drastic change, that’s sure to be:
Where once was ice, there’s only sea.

The Arctic’s paradigm’s been ice,
But fossil fuels extract a price:
The polar ocean quickly warms–
More balmy winds, more vicious storms–
And nowadays, with all that heat,
That paradigm is obsolete.
(Soon, all the ice we’ll see, methinks,
Will be inside our frozen drinks.)

i initially predicted on someone’s blog 4.9 because I was taken in by the Bering sea and did not expect to see especially warm conditions. I like being conservative so I am going to go with 4.4 now just because I am swayed by the peer pressure here. My actual guess would be between 3.8 and 4.6 but that is kind of wimpy. I also don’t WANT the arctic to melt. But I will be happy to shove it down Steve Godard’s throat if it is a new record, as he has been beyond arrogant about it being nearly impossible this year.

My prediction (using Gaussian Process regression) for NSIDC average extent for September 2012 is 4.584938 +/- 1.031588 M km^2. I suspect this is likely to be a mildly optimistic prediction, as it is based only on the September average extents, and pays no attention to the evolution of sea ice extent since September 2011.

NSIDC sept avg extent – 4.21MM sq km
Cryosphere today daily area min – 2.45MMsq km
The ice pack is already much more fractured than the 2007 minimum, but I’m guessing this will impact area more than extent. Extent may not even break the record.

Just posted basically the same thing on the Arctic Sea Ice blog without seeing this..

It’s really disturbing to see the difference between 2007, where there was a big retreat but the remaining pack was solid (and the biggest anomaly was due to very late re-freeze), and 2012 where it’s looking more and more like a slush puppy.

Goodness only knows what would happen if there were sustained 2007-type conditions in any future melting season. Actually, I suspect we know exactly what would happen.

Perhaps one question: Are we entering the period, when extent becomes less reliable measure than area for the actual amount of ice (note that extent was chosen because measurement of area can introduce errors due to difficulties in determining exact percentage of ice in given pixel) ? I mean if variability in how ice is spread is greater than error in determining pixel percentage, shouldn’t this make extent less reliable measure than area- I am comparing both measures, because they are performed by same instruments ?

– Sea ice area would be 1 million square kilometers – nearly nothing on the maps.

– But sea ice extent would be 5 million square kilometers.

So yes, as we approach zero volume and area, with just scattered sea ice around the pole, we could have a strange situation with apparently ‘healthy’ extent, but other indices being indistinguishable from zero.

Indeed. It’s quite possible that there is an area around the pole that has a physical propensity to harbour fragmented ice, and that is somewhat resilient to alterations in the density of the distribution of the ice as long as that density exceeds the arbitrary 15% definition.

For similar reasons area is not as informative as volume, because physical, threshold-type processes in winter and during melting somewhat camouflage the underlying loss of total ice mass.

Those inclined to only monitor extent are likely in the future to be caught by surprise.

Extent is an excellent metric, for its purpose. It’s just that this isn’t its purpose.

Extent dates from when precision measures were much more difficult to obtain, and is not exactly climatological in its nature. Its more navigational. Its important to boats sailing on the pack margin to know where they are likely to find ice that they cannot easily divert around. In the example, yes, there is a 5 million sq km area where you are likely to find ice that may be hazardous to navigation. Thats useful information for some. Its just not the best metric for measuring the “health” of the pack.

A worthy clarification Frank. It just goes to emphasis that there are horses for courses.

A similar thing could be said about the temperatures obtained from many CONUS stations – they were intended to inform about local temperatures at the time of recording, and not to describe global temperature trends, no matter that many try to confabulate the two purposes.

At least here most of us aren’t assuming that extent as a parameter best describes Arctic ice-mass dynamics!

August report coming soon, the deadline was this week. In that most of its contributors are scientists, competing to offer their best guesses and rationales regarding a specific indicator (NSIDC mean Sep extent) that will arrive pretty soon, the Web-based SIO strikes me as a worthwhile innovation offering a public glimpse of science as process.

If any website’s own reader polls comes out right there will no doubt be bragging, and why not. I suspect Tamino plans to cast a keen statistical eye on our estimates, turning those variables into knowledge as well.

Obviously we need Piers to properly divine how some vague measurement of solar wash millions of miles away will end up dissipated around the globe months later and affect weather right down to specifics at the regional level. And also whether I’ll meet my future bride to be this week.

I wouldn’t dare suppose any such skill for myself. I’ll only predict that the summer ice minimum will continue the long term trend of spiralling into oblivion.

Being an uneducated 50 yr. old HS grad. and having lost the WUWT forecast site and google this year seams to be also ignoring it, I will give my best shot (cheating by waiting this late). Based on the fact that the waters around the Arctic seem to be very warm this year, the winds seem to be blowing toward the east side of Greenland (Frams Straight?), based and that blender action of last week, and my living near Toronto where the temp seems to still be on the high side (oh forgot that is my imagination because Watts assures me that all thermometers are broken in NA). I will place a guess that come late Sept (and maybe into Oct) the extent will come in under 3.2 sq km and the area under 1.6 sq. km.
BTW this is best site for good ice info and nothing beats wuwt for giving me a terrific laugh.